Do Bats Hibernate In the Winter?

Do Bats Hibernate In the Winter?

Bats do they hibernate? If you haven’t spotted any bats throughout the autumn or winter nights, you could be asking yourself this question.

In the winter, certain bat species do hibernate. They will enter what is known as protracted torpor, a state of dormancy. Bats are able to lower their body temperature, metabolism, and heart rate during this sort of hibernation. In order to endure the hard winter, bats hibernate for six months (183 days).

Everything you need to know about what bats do during the winter will be covered in this tutorial.

All right? So let’s get going.

Bat Torpor Vs Bat hibernation

Both torpor and hibernation are considered to be forms of dormancy. Depending on their surroundings, bats are capable doing both.

Let’s examine each latent condition and when bats employ it.

Bat hibernation

Bats employ a particularly deep kind of dormancy known as hibernation during the winter.

During their hibernation period, bats will:

  • Reduce their heart rate to 4 beats per minute, at most.
  • Their core temperature should be reduced to about 35.6°F (2°C).
  • Reduce their breathing to 5 breaths per minute.
  • Abolish food digestion

All of these vital bodily processes can be slowed down by bats, which allows them to conserve as much energy as possible. They are aware of how limited food resources are throughout the winter. Additionally, winter weather can be dangerous.

Bats may survive the winter months by entering a state of hibernation. A bat’s hibernating period typically lasts six months out of the year.

A bat will begin to exhibit hibernation characteristics in response to a shift in temperature and a shortage of insects. The typical hibernation period for bats lasts from November to March. Depending on when the daytime temperature rises beyond 50°F (10°C), this may lengthen or shorter.

Bat Torpor

Consider torpor to be a milder kind of hibernation. Torpor allows bats to reduce their energy needs for bodily processes, though not as drastically as during hibernation.

When a bat enters torpor, it will:

  • their heart rate to between 4 and 80 beats per minute.
  • 90% less oxygen consumption

A bat’s body temperature won’t drop as much while in torpor as it does while hibernating.

Any time of year when the weather is bad, a bat will typically go into phases of torpor. A bat enters a state of torpor if the temperature drops below 50°F (10°C) for a few days.

This is due to the fact that insects are less active when the weather is bad. There is less energy when there is no food source. The greatest method for bats to conserve energy is to not use up the energy they already have.

Similar to hibernation, brief periods of torpor are an energy-saving survival tactic. With bats, this torpor often only lasts one day.

Do bats Wake during hibernation?

Despite their six-month hibernation phase, bats are active. Sometimes they will awake. Depending on the kind of bat, this will happen occasionally. Some bat species only awaken once every 4-6 weeks, while others do so once each week.

Because of this, hibernation in bats is effectively a series of extended bouts of torpor strung together.

A bat will briefly forage for insects, drink, and eliminate pee and excrement after it awakens from hibernation. They’ll emerge from hibernation immediately after returning.

For bats, these awake times might be hazardous. Even for brief durations of up to an hour, waking a bat requires a lot of energy.

They might be unable to enter hibernation again if they expend too much energy. They then run the risk of starving to death or freezing to death in the winter. Additionally, they face the risk of rousing other bats that are hibernating too early.

How Do Bats Prepare For Hibernation?

For bats, hibernation is more difficult than you may imagine.

They are in quite a risky situation right now, and if they aren’t adequately prepared, they might even perish. For the species to survive, hibernation preparation over the summer and fall is crucial.

The four primary ways that bats get ready for hibernation are as follows. Let’s look at it.

1. Fatten up

Insects are a major source of food for bats during the summer. To gain as much fat as they can is one of the reasons they do this. These fat reserves are a specific brown fat made for the winter instead of your standard white fat.

Bats will use the brown fat they store now as an energy source when they are hibernating. During torpor, the bats won’t use a lot of the fat. For bats, though, the time when they awaken requires a lot of energy.

The bats can wake up and go back into hibernation if they have a sufficient amount of fat reserves.

A bat’s body weight will increase by 25% to 30% as it gets ready for the winter.

2. Find a good location

Bats need to locate a suitable area for hibernating. They require a calm, cool environment with steady temperature and humidity levels. These final two sentences are crucial.

Bats prefer the dim conditions of mines, quarries, bridges, abandoned structures, tunnels, and attics. These areas will safeguard bats from unpredictable weather and keep them from being readily disturbed.

A hibernacula is the place where a bat hibernates. Bats frequently come back to exploit effective hibernacula for many years.

41°F (5°C) is the ideal temperature for a bat hibernaculum. As a result, bats can maintain a cool temperature while hibernating. To ensure that bats don’t lose too much water during hibernating, the ideal humidity is crucial.

Additionally essential to their survival is the need to minimize disruption. Bats wake up too early and use too much energy when there is disruption. It’s possible that a disturbed bat won’t be able to awaken from hibernation. They might starve to death or freeze to death if this occurs during the dead of winter.

3. Huddle Together

3. Huddle Together

The following benefits of this gathering habit for bats:

  • maintaining constant humidity and temperature
  • Weather-protective shelter
  • safeguarding from predators
  • Increasing the rate of conception

These bat colonies are referred to as populations. A colony of bats may have twenty or thousands of them. There will typically be hundreds of bats in a colony.

When assembled in their colony, bats will slumber on their backs. Roosting is the action in question. The purpose of roosting is to allow bats to congregate more densely for increased protection.

4. Grow Fur

Once a year, bats will molt and grow new fur. Around the summer and fall, this occurs. Accordingly, bats that overwinter should have new fur for hibernating.

The process of hibernation requires bat fur to be present.

Bats with fur do more than just keep their water from evaporating. Additionally, it helps facilitate the process of emerging from torpor stages. A bat must swiftly increase its body temperature from about 35°F (2°C) to 106°F (41°C) when it awakens.

Bats can accomplish this without wasting their valuable heat thanks to their thick coat of fur. Additionally, the fur shields bats from heat loss and excessive energy expenditure while they are awake for brief periods of time.

Do all Bats Hibernate?

Not all kinds of bats hibernate throughout the winter. To live, some bats go to warmer regions. Warmer climates offer better survival conditions and a plentiful supply of insects to eat.

A few bat species will move and hibernate. Others might not hibernate or move. This happens more frequently to bats living in states with warm winters, such Southern Texas or Florida.

species of batHibernateTravel from the USABoth
Dark Brown Bat  x
a smaller-nosed bat x 
Black Batx  
Brown Big Bat  x
stale bat x 
Observed Bat  x
White-Haired Bat  x
Pipistrelle Sopranox  
fluttering bats x 
Dark batsx  

Helping Bats Survive the Winter

There are a few things you can do to ensure that bats in your neighborhood make it through the winter.

1. Hang a Bat Box

A fantastic option to give bats a secure place to sleep throughout the winter is to hang a bat box in your yard.

It is much preferable to mount a bat box on the side of your home as opposed to a tree or a pole. Although bats will use the boxes in these locations, doing so puts them at danger from predators.

By hanging a bat box on your property, you can help stop the bats from really making your house their home and causing harm.

Installing two or more bat houses in the same area will increase your chances of attracting bats. Bats choose dark-colored bat boxes as well.

Check out this best-selling bat home if you’re looking for a high-quality structure to keep bats warm during the winter.

2. Attract Insects

Insects are hard to find in the cold. However, we are aware that they prefer to hide under underbrush. You can maintain tiny flower and vegetable gardens, log piles, or flowerbeds in your yard.

This will give bats a fantastic location to hunt for insects. Insects will eat more and conserve energy during their brief awake periods if there is a plentiful supply of food available.

3. Landscaping

The best strategy to aid bats during the winter is to have a large number of plants, trees, or shrubs in your yard.

These will serve as landmarks for bats as they navigate your yard. They navigate around using echolocation, which explains this. The more energy they can conserve by not flying around, the easier this will be for them.

The bats will be able to find plenty of insects in your yard’s vegetation.

4. Do Not Disturb

Do not attempt to move a bat that is roosting if you discover it during the winter. You or your home won’t be harmed by a bat that is hibernating.

The bat may not make it through the winter if you disturb it. The ideal time to disturb a bat in hibernation is in the early spring. At this stage, it is safe to evict them if you must because they will have a food supply to eat.

Final Thoughts

Final Thoughts

The winter hibernation of bats requires preparation. They do this because they require the energy to briefly awaken. Bats can forage, drink, and urinate during these waking times.

To help them survive, bats will hibernate in vast colonies, thus they must be selective about where they hibernate. They will be in the ideal circumstances to have the greatest chance of surviving as a result.

There are several ways you may support bats this winter. This mostly consists of giving habitat and access to a reliable food source. For additional details on how to draw bats to your yard, see my guide.

Winter is a critical time to avoid disturbing bats that are hibernating because doing so could cause the bat to starve or freeze to death.


Do bats come out in the winter?

Occasionally throughout the winter, bats awaken to move about a little or to adjust to rapid changes in temperature if their location becomes too warm or too cold. They now have the opportunity to exit the crawl area and enter the house.

Will bats leave your house in the winter?

However, certain species—the large brown bat being a notable example—will hibernate within structures over the winter. Most migratory species of bats in the northeast depart colonies for winter hibernation sites during the first week of September. So the best time to remove bats is in the early autumn.

What to do if you find a bat in winter?

Put on gloves and place a container over the bat that is perched. Scoop the bat into the container. The bat can be let outside if the weather is above freezing and should be able to locate a new location to hibernate—hopefully not back in the attic this time—under some bark or a hole in a tree. 

What do you do with a bat in your house in the winter?

If it’s considerably below freezing outside, you can keep the bat in a box overnight until it warms up during the day, then release it then. As they would quickly dehydrate in the warm conditions of the house, bats shouldn’t be kept in confinement like this for an extended period of time.


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Sarah Green

Wildlife and Nature Fan & Author